The present invention relates to a crane controller for the semi-automatic control of a rotary crane.
In the semi-automatic control of a crane, the operator will provide a desired slewing speed and/or a desired luffing speed as an operator input, and a model-predictive reference trajectory planning module of the crane controller will calculate a reference trajectory that obeys the system dynamics and follows the operator input. This reference trajectory will be used by a feedforward-controller for controlling the slewing actuator and/or the luffing actuator of the crane.
The trajectory planning module will use a physical model of the crane and/or of the load hanging from the crane, in order to generate a reference trajectory that obeys the system dynamics. Further, the reference trajectory planning module will use an optimization unit for calculating a reference trajectory that follows the operator input as quickly as possible.
In prior art crane controllers of this type, the optimization unit also takes into account the system limitations of the crane, in order to calculate a reference trajectory that the crane actuators can create. Further, it is known to use feedforward-controllers having anti-sway-control properties, and which take into account the pendulum dynamics of the load hanging from the crane in order to limit a swaying of the load during the movement of the crane. Further, some approaches try to minimize the acceleration of the load during optimization.